carhart



H. A. CAHHART.

COMBINED IYPEWRlTING AND COMPUTING MACHINE.

APPLICATION FILED APR-13,1917- Patented Feb. 3, 1920.

2 SHEEIS-SHEET INVEN T n R JKM M M H: ATTORNEY H. A. CARHART.

COMBINED TYPEWRITING AND COMPUTING MACHINE.

APPLRCATION FILED APR. 13. 1911,

Patented Feb. 3,1920.

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lNVEN TEIR WITNEESEE Hus ATTORNEY and combinations and arrangements of.

UNITED STATES PATENTOFFICE.

HERBERT CARHART, OF SYRACUSE, NEW YORK, ASSIGNOR TO REMINGTON TYPE- WRITER COMPANY, OF ILION. NELV YORK, A CORPORATION OF NEW YORK.

COMBINED TYPEWRITING AND COMPUTING MACHINE.

Specification of Letters Patent.

Patented Feb. 3, 1920.

Application filed April 13, 1917. Serial No. 161,769.

T 0 all whom it may concern:

Be it known that I, HERBERT A. CARHART,

citizen of the United States, and resident of Syracuse, in the county of Onondaga and State of New York, have invented certain new and useful Im rovements in Combined Typewritin and omputingv Machines, of which the ollowin is a specification.

My invention re ates to computing machines and especially to combined typewriting and computing machines, and it has for its principal object to provide means whereby two separate keys, which keys may be adapted for writing different characters, can be connected to the same part ofthe computing mechanism so as to cause the same di it to be registered. In some instances this invention is useful for writing and registering fractions, one set of keys being eonneeted up to write digits, and the other set of keys being connected up to writefractions, and both sets of keys-being connected with the computing mechanism. The invention is also useful where it is desired to distinguish different items -by writing them in different styles of type. For example, one set of keys can be connected up with roman types and the other set with gothic types, so that one sort of items can. be written in one style of type, and the other in the other style, and both items will be registered alike in the computing mechanism; and the invention may also have other applications.

To the above and other ends my invention consists incertain features of construction parts, all of which will be fully set forth herein and particularly pointed out in the claims.

One embodiment of my invention is illustrated in the accompanying drawings, in which Figure 1 is a front to rear vertical sectional view of so much of a combined typewriting and computing machine as is necessary to illustrate the embodiment of my invention therein.

Fig. 2 is a plan view of the keyboard and some of the connections, with parts broken away and parts shown in section.

Fig. 3 is a fragmentary view of a portion of the connections from one pair of keys to one of the elements of the computing mecha- IllSIIl.

Fig. 4 is a fragmentary rear view of the same.

Fig. 5 is a perspective view of one of the bell crank key levers and its immediate connections.

Fig. 6 is a partial vertical section of the actuator Figs. 1 and 2 are on a reduced scale and Figs. 5 and 6 are enlarged views.

I have shown my invention embodied in a Smith Premier-Wahl machine, said machine consisting of a Smith Premier N0. 10 typewriter having the VVahl computing mechanism attached thereto. Not only are the Smith Premier typewriter and the Whal computing mechanism both well known in the art, but the. combined machine has been on the. market for some time and is in extensive use; and it has therefore not been deemed necessary to show all of the details of the typewriting and computing mechanisms in the drawing.

The main frame of the Smith Premier typewriter comprises. among other things, side plates 1, a top plate 2, and a keyboard plate 3. A platen 4 is mounted on a traveling carriage, not shown. The machine has two sets of type bars, namely, shorter type bars 5, vpivoted by ball hearings on a segment 6, and longer type bars 7, similarly pivoted .ona second segment 8. Each of said type bars carries a single tvpe 10, the machine not being provided with any case shift mechanism. The type bars are actuated by a, series. of connections including links 11 radially arranged and pivoted at their outer ends to subdevers 12, which sublevers are pivoted at 13 on a segment 14. Each of said sub-levers is provided with a returning spring 15 and they all operate a universal bar 16 which is connected with the carriage escapement and with the ribbon vibrator. The sub-levers 12 are operated by links 17 extending toward the front of the ma hine beneath the keyboard where each of them is connected with the depending arm of a bell crank key lever 18, which ell crank also has a rearwardlv extending arm to which is connected the stem 20 of one of the printing kevs. For the purposes of this case said printing keys may be said to be f in Fig. L'has a stem 27, which is connected with a guide link 28 and also .with an arm 30 projecting from a rock shaft 31 extending from the frontof the. machine. toward the rear thereof, and in the rear part ofthe machine connected, with the escapement mechanism. This rock shaft is not fully shown and its connections are t d, these being old and well-known parts of the machine.

In those forms of the Smith Premier typewriter on which the Wahl adding mechanism has been mounted the keyboard has been modified from its standard form by placing the numeral keys 23 in a separate row in front of the back space and margin release keys and the space bar. In the present instance the fraction-printing keys 22 are shown included in the next row of keys back of the space bar, etc. The character keys 21 are shown adaptedfor printing capital'lctters, various punctuation marks, etc., and also combinations of letters constituting abbreviations useful in billing; but this entire arrangement can be varied, as far as the present invention is concerned.

The bell cranks 18 of the digit keys 23 are pivoted on a wire 32 mounted in brackets 33, said brackets being mounted in an inclined extension 34 of the keyboard plate at the front of the machine. In practice this extension also serves to support the tabulator keys and the scale plate therefor, but as these parts have no particular connection with my present invention they have not been shown.

As shown in Fig. 1 each of the key stems 20 has a collaror flange 35 adapted to strike against a pad 36. These pads consist of strips of felt, one strip for each transverse row of keys, and said strips are mounted in channel bars 37 of sheet metal.

The Wahl adding mechanism has a stationary framework comprising a transverse bar 38 which is supported from the top plate 2 of the typewriter by means of two brackets 40. each of which is secured to said top plate by screws 41 and to said cross bar 38 by a screw and nut 42. Said framework also comprises end plates 43 and various other parts which it is not deemed necessary to illustrate or describe in detail in this case. That part of the Wahl mechanism which is called the actuator includes a master wheel 44 which: is operated by a segfor each digit and each havin a shaft there are also mounted arms 45, one in or roller 47 adapted to be engage an operated by a key actuated goose-neck cam 48. There is a series of these cams 48, each pivoted on a transverse frame rod 50, and each having pin-and-slot connection 49 with a digital sector 51, the series of which sectors are also pivoted on said rod 50, one such sector by the side of each of the cams 48. The pin and slot 49 constitute a lost motion connection between each sector 51 and its adjacent cam whereby the cam is operated by the sector. The sectors 51 are operated by vertical links 52, each pivoted at its upper end to one'of'said sectors forward of the rod 50 andeach at its lower end connected with a numeralprinting key. As there is one sector 51' for each digit, these sectors may be called digital elements of the computing mechanisnn The computing mechanism also comprises a universal bar 53 which is mounted on arms 54, each rigidly connected with a transverse rock shaft 55; and each of the sectors 51 has a: projecting portion 56 adapted to operate said universal bar. The construction is such that when a numeral key is depressed and the corresponding link 52 is pulled down ward, the projection 56 of the sector moves the universal bar 53 downward and toward the front of the machine to its first operated position. As the. key stroke continues a concentric edge of the projection 56 rides under the universal bar, holding said universal bar stationary in its operated position until almost the extreme end of the down stroke of the key. at which time the projection 56 moves entirely away from the universal bar, leaving the latter free to be moved by a certain sprina back to its normal position shown in Fig. 1. ,On the up stroke of the key the projection 58 again encounters the universal bar 53 and moves the latter upward to its second operated position. when said universal bar again rides on the c011- centric edge of the projection 56, where it remains until the end of the return stroke of the parts. At this time said universal bar again escapes from said projection 56 and drops back to its normal position. During the greater part of the down stroke of the key. therefore, the universal bar is held in its forward or lower operated position and during the greater part of the up stroke of the key it is held in its upper operated position. This universal bar performs several functions in the VVahl machine, one of them being to control full stroke mechanism for the sectors 51. Each of said sectors has two sets of ratchet teeth, a lower set 57, and an upper set 58. the former coiiperating with a pawl 60. and the latter with a pawl 61. each of said pawls consisting of a long bar of sheet metal extending transversely of the machine and mounted on a square bar or rock shaft 62. An arm 63 projects from the lower rock shaft 62 into proximity to an arm 64 on the universal bar frame in such osition that when the universal bar is moved ownward and forward on the down stroke of the key said arm 64 will rock the pawl 60 downward to an inoperative position; but when the universal bar escapes from the projection 56 at the end of the down stroke of the key this pawl will be drawn up by a spring 59 so as to engage the ratchet teeth 57 and prevent downward movement of the key after said key has begun its up stroke. The upper rock shaft 62 has an arm 65 which lies above an arm 66 on the universal bar frame in such osition that when the universal bar is roc ed upward at the beginning of the up stroke of the key the pawl 61 will be lifted out of engagement with the ratchet 58. Said pawl engaging said racket on the down stroke of the key prevents upward motion of the key once it has started its down stroke until said pawl is lifted as described at the beginning of the up stroke. All of this mechanism is included in the familiar Wahl computing mechanism.

Said Wahl mechanism also includes a carriage 67 mounted on various rollers 68 which are journaled to the stationary framework of the lVahl machine. On said carriage one or more totalizers 70 can be mounted, each of said totalizers including a series of wheels 71 adapted, when the computer carriage is suitably located, to mesh with the master wheel 44. The carriage 67 is suitably connected with the typewriter carriage so as to travel back and forth in unison therewith.

The connections from the links 52 to the numeral keys include certain bell. cranks which are mounted on an angled frame bar 72 extending across the base of the machine and secured to lugs 73 on the side plates 1. To the rear vertical face of this bar there are secured a series of brackets 74 each having cars 75 bent out rearward therefrom to accommodate a ivot rod 76, and between each pair of ears 5 there are pivoted on said rod a pair of bell cranks 77, said bell cranks having their rearwardly extending arms lying close together and side by side. Each of said bell cranks is struck up out of sheet metal, and, as best shown. in Figs. 3 and 4,

' it is formed with a connecting bar or yoke piece 7 S which connects the rearwardly ex tending arm with another arm or car bent off from said yoke piece and perforated and pivoted on the rod 76. Each of the two hcll cranks is thus pivoted on said rod at two points spaced apart. one of said points being where the rod passes through the main bodv of the bell crank and the other where it passes through the laterally spaced, car 80. A light returning spring 81 coiled around the rod 76 has one end engaging the cross bar 78 and the other the frame bar 72. Each of the two bell cranks has a depending arm 82 which is connected by a link 83 with one of the key operated bell cranks 18. As shown in Fig. 4 the two arms 82 are bent off, the one toward the right and the other toward the left, in order to space them apart.

The rearwardly directed arms of the two bell cranks 77 of a pair lie side by side, and each of them is prolonged downward into an arm 84 having therein a slot 85 which slot is in an arc concentric with the pivot rod 76 and said slots are closed at the top. The link 52 is bifurcated at its lower end, having two branches 86 which straddle the two arms 77, one of said branches lying against the right-hand face of the righthand bell crank, and the other against the left-hand face of the left-hand bell crank; and a pin 87 joining *saidtwo branches 86, passes through the two slots 85. The construction is such that if either of the two bell cranks be operated the in 87 and link 52 will be pulled downward by the closed upper end of the slot 85 of the operated bell crank, said pin movin freely downward through the slot 85 of t e tin-operated bell crank. In Fig. 3 the bell crank nearest the observer is shown operated, and the other one is in its normal position.

The link 83 of one of the bell cranks of a pair is connected with the key lever 18 of one of the digit keys 23, and the link 83 of the otherbell crank of the same pair is connected with the key lever 18 of one of the fraction keys 22 so that the link 52 will be ulled downward if either of these two keys is operated. In the present instance the keys 22 are shown adapted for writing and addin eighths and it will be noted in Fig. 2 that t e key 22 is directly back of the l kev 23, the 1 ke 22 is directly back of the 2 key 23; an it will also be understood that the 3* key is directly back of the 3 key, the key is directly back of the 4 key, and so on. The Wahl adding machine can be provided with totalizers 70 arranged to add and subtract numbers, the extreme right-hand wheel of-the totalizer being arranged to add and subtract eighths, this particular wheel being connected up to transfer to the units wheel after eight units of rotation, whereas all of the other wheels are arranged to transfer after ten units of rotation. The described connections are such that the key willoperate the computing mechanism, t,urning the master wheel l4 one tooth, the key will turn the master wheel two teeth, and so on, but it will of course be understood that these fraction keys are used only when the fractlous wheel 0! the tctalizer 70 is in mesh with the master wheel. At all other times the digit keys 23 are used. In the present instance there are only seven of the keys 22 but in case said keys were used to write not fractions but, for exam le, gothic numerals, then ten such keys W0 (1 of course be provided.

The construction of those bell cranks 18 that are connected with the computing mechanism will be understood from Fig. 5. All of the key levers of this machine are pivoted at 88 on rods or wires that run through frame pieces 90, 2, consisting of strips of sheet metal set on edge and lying beneath the keyboard 3. Each of the key levers consists of two branches connected together by a yoke piece 91, Fig. 5, so as to have each key lever pivoted on said wire at two points spaced apart. Each of said branches has a forwardly extending arm 92, and the lower end of the key stem 20 is embraced between these two arms to which it is pivoted'at 93. In the ordinary Smith Premier vmachine only one of the branches of the bell crank has a depending arm 94 to which the type bar operating link 17 is pivoted but when the adding machine is used the other branch is also formed with a depending arm 95 to which the link 83 is pivoted. In the present instance the key levers 18 corresponding to each of the keys 22 and 23 are constructed substantially as shown in Fig. 5, one of the depending arms being connected to a type bar and the other to a bell crank 77. It will be understood that one of the two bell cranks 77 of a pair is connected with one of the keys 22 and the other with the corresponding key 23. The keys 23 for writing 8, 9, and 0 are connected with individual bell cranks 79 similar to the bell cranks 77 but having the link 52 merely pivoted thereto instead of connected by means of the pin and slot 87, 85.

It will be recalled that the sectors 51 of the Wahl actuator are controlled by a full stroke device to compel a complete operation of one of these sectors on its positive stroke before its return stroke can begin and also a complete return stroke before another positive stroke can begin. The Wahl machine is also provided with a key arresting device which prevents the o eration of another sector 51 while one 0 said sectors is out of normal position. The whole construction is such that if one of the numeral kevs be partially depressed but not fully operated, all of the remaining numeral keys of both sets, viz., the keys 22 and 23, will be locked against operation until that one ke has completed both its down stroke and its up stroke. On account of the pin-andslot connection between the link 52 and the bell cranks 77, however, -if the operator should partially depress one of the numeral or fraction keys and then remove his finger, the key would return to normal position, notwithstanding the sector 51 and link 52 straight down to a point were held by the full stroke device in their partially operated positions. Under these conditions the operator-would find the machine locked up but if all the keys had returned to normal position the keyboard would not show what key it was that had been only partially o erated, and unless the operator remembere what key had been last struck he might have to try all of the keys to find out which one was causing the trouble. In order to hold the finger key 22 or 23 also .illdt-S partially depressed position under these conditions I have provided means for locking together the bell crank 77 and the link 52 soon after the beginning of the stroke of said bell crank and link. To this end each of said bell cranks has a pin .96 projecting from the side thereof above the upper end of the slot 85, the two side pins of a pair of bell cranks projecting in opposite directions as will be understood from Figs. 3 and 4. Each branch of the bifurcated end 86 of the link 52 extends which as shown in Fig. 1 normally stands a little above the pin 96, and said branch 86 is thence formed with a curve 97 extending toward the rear and forming a horizontal shoulder 98 a little above and back of the pin 96. When the bell crank is operated and the link 52 is drawn downward the pin 96 moves in under the shoulder 98, as shown in Fig. 3, with the result that the bell crank and the link are positively locked together against relative motion either upward or downward, such. locking being due to the combined action of the pins 96 and 87, one of which prevents relative motion in one of said directions and the other in the other of said directions. If, now, the key be only partially depressed and the link 52 be held down by the full stroke mechanism of the actuator, the bell crank 77 will also be held down by reason of the engagement of the pin96 with the shoulder 98, and the key will be held down by its connection with the bell crank. If the key be only partially depressed therefore it will remain in its partially depressed position so that the operator can see which key it is that has been only partially operated.

When the keys are all in their normal positions however, the links 52 are held up by light returning springs 99. each connected at one end to a link 52 and at the other end to a stationary part of the machine. said springs in the present instance being shown connected to one of the channel bars 37.

The Wahl actuator is provided with key arresting mechanism adapted to prevent the operation of more than one of the sectors 51 at a time. As this mechanism is well known I have not illustrated it in detail,

but it comprises a series of plates or pendants 100 pivoted to a transverse frame bar eration.

101 of the actuator and the two plates 100 at the ends of the series are connected together by a. tie-bar 102. The construction is such that when one of the sectors 51 is operated by its link 52 it passes between two of the plates 100, which plates are so s aced as that there is enou h lost motion in t e whole series to admit oi the passage of one of the sectors and no more. It results from this construction that when any one of the numeral keys 22 or 23 is operated, all other sectors 51 than the one connected with said key are locked against operation and therefore all of the numeral keys connected with said locked sectors are locked against operation including both the fraction keys 22 and the digit keys 23. Not only are all of the numeral keys of both series that are connected to sectors 51 other than the operated sector locked against operation, but also when said sector 51 is o erated by one of the two keys connected t erewith the other of said two keys is also looked a ainst op- This will be ereeived y an inspection of Fig. 3 whic shows the position of the parts when one of'the keys is partially depressed. In this figureone of t e levers 77 connected with the link 52 is shown partially operated and it will be perceived that one of the branches 86 of the lower end of said link stands in the path of the pin 96 of the un-operated lever 77, with the result that this lever is also looked against complete operation. It will thus be perceived that when any one of the keys 22 or 23 is in depressed position all of the other keys of both sets are locked against operation.

Various changes can be made in the details of construction and arrangement without departing from my invention.

What I claim as new and desire to secure by Letters Patent, is:

1. In a computing machine, the combination with computin mechanism comprising digital elements, 0 two sets of ke s, two sets of types controlled respectively y said two sets of keys, and means whereby keys of both sets control the same digital element alike, the keys of one set independently of those of the other set.

2. In a printing and computin machine, the combination of printing mec anism including types and computin mechanism, of two sets of numeral keys, t e keys of one set controlling different types from those of the other set, and means whereby the keys of each set control the computing mechanism the same as keys of the other set and independently of the keys of the other set.

3. In a combined typewriting and computing machine, the combination with typewriting mechanism including types and com uting mechanism including differential mec anism, of two numeral keys connected respectively to print from different types and means whereby both of said keys control the same part of said difierential mechanism alike and each independently of the other.

4. In a computin and printing machine, the combination wit com uting mechanism including differential mec anism and printing mechanism, of a series of keys connected to said printing and computing mechanism to write and re 'ster whole numbers, of another series 0 keys connected with said printing mechanism to print fractions and connectedwith the same parts of the computing mechanism as the said whole number eys, the keys of the two series operating indepndently of each other.

5. In a computing machine, the combination with computing mechanism comprising digital elements,-of two sets of keys for controlling said computin mechanism, one of said digital elements liaving two connections, one to a key of each set and each of said two connections and said digital element being capable of operation independently of the other connection, a full stroke device for said digital element, and means whereby either of said keys when 0 erated becomes positively connected with said di tal element whereby said key comes un er the control of said full stroke device.

6. In a computing machine, the combination of two sets of keys, levers 77 operated by said keys and arranged in pairs, the levers of each pair being connected with a key of each set, and a single connection 52 operated by the levers of each pair.

7. In a computin machine, the combination of two sets of eys, levers 77 operated by said keys and arranged in pairs, the levers of each pair being connected with a key of each set, a single connection 52 operated by the levers of each pair, and means whereby either lever when operated becomes positively connected with said connection 52.

8. In a computin machine, the combination of two sets of eys, levers 77 operated by said keys and arranged in pairs, the levers of each pair being connected with a key of each set, a single connection 52 operated by the levers of each pair, means whereby either lever when operated becomes positively connected with said connection 52, and full stroke mechanism controlling said connection 52.

9. In a computingI machine, the combination of two sets of eys, levers 77 operated by said keys and arranged in pairs, the levers of each pair being connected with a key of each set, a single connection 52 operated b the two levers of a pair, means whereby either lever when operated becomes positively connected with said connection 52, and means for preventing the simultaneous operation of two keys.

10. In a computing machine, the combination with computing mechanism including digital elements, of two sets of keys connected with said digital elements in pairs, one key of each set havi a pin-and-slot connection with each digital element whereby said element can be operated by each of said keys independently of the other.

11. In a computing machine, the combina tion with computing mechanism including digital elements of two sets of keys connected with said digital elements in pairs, one key of each set havin a pin-and-slot connection with each digita element whereby said element can he operated by each of said keys independently of the other, and means whereby each of said keys when operated becomes positively coupled to said digital element.

12. In a computing machine, the combination with differential mechanism including a digital element, of two numeral keys, two levers one operated by each of said keys, 2. link connected with said digital element and havin pin-and-slot connection with both of sai levers, and positive coupling means including a pin and a shoulder for positively coupling said link to one of said levers when the latter is operated.

13. In a computing machine, the combination with diiferential mechanism including digital elements, of two keys, two levers one operated by each of said keys and each of said levers having a slot, a link connected with said digital element and having a pin passin through both of said slots, and pins on said levers and shoulders on said link, a pin and shoulder cooperating when one of the levers is operated to couple said lever positively to said link.

14. In a computing machine, the combination, with computing mechanism includin digital elements, of numeral keys arranged in pairs, a pair of keys for one digital element, two levers connected with said keys and arran ed side by side, and a link connected wit a digital element and havin pin-and-slot connection with both of said levers.

Signed at Syracuse, in the county of Onondaga, and State of New York, this 11th day of April A. D. 1917.

HERBERT A. CARHART.

Witnesses:

J. B. HOLDEN, F. S. LEWIS. 

